Ehlers-Smoothed Stochastic Oscillator [Krypt]

This indicator is in principle similar to Stochastic Oscillator, but contains the following improvements:
- advanced Ehlers-based smoothing (typically results in earlier signals than regular EMA smoothing)
- graceful degradation when few candles present for improved accuracy in the beginning of the chart
- buy/sell signals based on K-D crossover above/below thresholds